It is well known to treat patients with medicaments contained in an aerosol, for example, in the treatment of respiratory disorders. It is also known to use for such treatment, medicaments which are contained in an aerosol and are administered to a patient by means of an inhalation device comprising a tubular housing or sleeve in which the aerosol container is located and an outlet tube leading out of the tubular housing. Such inhalation devices are generally referred to as metered dose inhalers (MDIs). The aerosol containers used in such inhalation devices are designed to deliver a predetermined dose of medicament upon each actuation by means of an outlet valve member at one end which can be opened either by depressing the valve member while the container is held stationary or by depressing the container while the valve member is held stationary. In the use of such devices, the aerosol container is placed in the tubular housing with the outlet valve member of the container communicating via a support with the outlet tube, for example a nozzle or mouthpiece. When used for dispensing medicaments, for example in bronchodilation therapy, the patient then holds the housing in a more or less upright condition and the mouthpiece or nozzle of the inhalation device is placed in the mouth or nose of the patient. The aerosol container is pressed towards the support to dispense a dose of medicament from the container which is then inhaled by the patient.
It is also known to use dry powder inhalation devices for the delivery of inhalable medicament. In one aspect, such dispensers comprise pre-metered doses of powdered medicament, for example in capsules or blisters. In another aspect, such dispensers comprise a reservoir of powdered medicament from which doses are metered prior to or concurrent with the delivery process. In either case, the device may be designed for passive release of medicament, where the medicament is simply made available at a delivery position for aerosolisation in response to the inhalation of the patient. Alternatively, an active release mechanism may be used whereby a ‘puff’ of compressed gas or air is provided to the delivery position to assist in aerosolisation of the powder prior to or concurrent with the inhalation of the patient. Such devices are generally called active release dry powder inhalers (active DPIs). The source of the compressed gas or air is generally an aerosol container.
It is also well known to use syringes for the delivery of injectable medicament to a patient. Traditional syringes rely on puncturing of the patient's skin by a hollow needle through which the injectable medicament (in solution or suspension form) is delivered to the muscle or tissue of the patient. Recently developed needleless systems for the delivery of injectables employ high velocity injection of particle formulated drugs or vaccine through the skin and into any physically accessible tissue. Other needleless systems employ similar high velocity injection of drug or vaccine coated on to a suitable carrier particle.
Other forms of medicament dispenser, such as bottles, tubes or vials, are known in the art, which comprise an exit channel (or nozzle) for dispensing medicament therefrom. In a typical dispensing operation using any of the above devices, the body of the device is held by the patient and the exit channel (or nozzle) of the device is placed in the mouth/nose or on the skin, or in the palm of the patient's hand.
When not in use it is desirable, from a hygiene standpoint, that the exit channel is provided with some kind of protective cover. The cover desirably acts both to prevent build-up of dirt on the exit channel and to prevent ingress of dirt into the body of the device through the channel, which might then be subject to administration by a patient. It is desirable for the cover to be joined to the body of the device so that it cannot be separated from the device.
Patient trials of various medicament dispensers have shown that patients do not always fully expose the exit channel before attempting to use the device or fail to fully protect it when the device is not in use.
The applicants have now found that this problem can be overcome by the use of a cover which has biasing means acting upon it. The biasing means enables the cover to move in a reversible manner directly from the in-use position, when the exit channel is fully exposed, to the storage position, wherein the exit channel is fully protected by the cover.
A further advantage of the present invention is that the exit channel cover is provided with a clear portion to enable viewing of the exit channel when the exit channel is fully protected. This clear portion also enables viewing of a dose counter or alphanumeric display when the exit channel is fully exposed.
The Applicants have also found that the present invention has utility in protecting the exit channel of a wide range of dispensers, including food and toiletry dispensers.